The present invention generally relates a gearless and oilless gas turbine engine, and, more specifically, to gearless and oilless rotors supported by several non-contact bearings used in combination with each other.
Conventional aircraft gas turbine engines use a complex oil lubrication system to lubricate rolling element bearings supporting the high speed shafting. Controls and accessories that support critical engine operation, such as the fuel and lubrication systems, cannot operate at the high shaft speeds and, therefore, must be geared down using complex mechanical gear trains. These conventional engine configurations are complex and result in high initial as well as high operational costs.
U.S. Pat. No. 6,367,241 concerns a pressure-assisted electromagnetic thrust bearing. The pressure-assisted electromagnetic thrust bearing is a hydrostatic bearing using compressor discharge air. The air is hot and, although some cooling may take place in the tube 70, the air increases the magnetic bearing operating temperatures, reducing its life and reliability. The compressor air is piped into air chambers 90 and, due to seal leakage, some of this compressed air may result in a loss to the engine thermodynamic performance. The pressure at altitude will be lower, thus reducing the thrust load reaction capability in the pressure-assisted fluid bearing (FIG. 2 of U.S. Pat. No. 6,367,241).
As can be seen, there is a need for a gas turbine engine having bearings that are simple in design, relatively small in size, and light in weight. Moreover, such a gas turbine engine should have bearings that adequately support the engine's rotors during both regular engine operations and during the various loads that are applied during aircraft flight maneuvers.